• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.189-193
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• 2008

A Gram-positive and endospore-forming strain, $JH8^T$, was isolated from deep-sea sediment and identified as a member of the genus Paenibacillus on the basis of 16S rRNA gene sequence and phenotypic analyses. According to a phylogenetic analysis, the most closely related species was Paenibacillus wynnii LMG $22176^T$ (96.9%). Strain $JH8^T$ was also facultatively anaerobic and grew optimally at $20-25^{\circ}C$. The major cellular fatty acid was anteiso-$C_{15:0}$, and the DNA G+C content was 53.1mol%. The DNA-DNA relatedness between the isolate and Paenibacillus wynnii LMG $22176^T$ was 7.6%, indicating that strain $JH8^T$ and P. wynnii belong to different species. Based on the phylogenetic, phenotypic, and chemotaxonomic characteristics, strain $JH8^T$ would appear to belong to a novel species, for which the name Paenibacillus donghaensis sp. novo is proposed (type strain=KCTC $13049^T=LMG\;237S0^T$).

• Korean Journal of Microbiology
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• v.47 no.1
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• pp.81-86
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• 2011

Xylanase is a class of enzymes that hydrolyze the linear polysaccharide ${\beta}$-1,4-xylan into xylose. This enzyme is applied in the process of paper making and may be used for the process of biofuel production in the future. The Paenibacillus donghaensis JH8, isolated from Donghae deepsea sediment and reported as a novel bacterium, was known to degrade xylan and its xylanase was characterized in this study. The enzyme was maximally induced in the presence of 0.1% xylan. The production of xylanase was started at early logarithmic phase and reached about 55 miliunit at stationary phase of growth. The optimal temperature and pH of extracellular xylanase were found to be $40^{\circ}C$ and pH 6.0, respectively. The activity of xylanase was inhibited by the presence of $Ca^{2+}$, $Mn^{2+}$, $Fe^{2+}$, $Cu^{2+}$, $Al^{3+}$ or EDTA, and activated by $K^+$, $Ag^+$ or DTT. This xylanase was stable at $40^{\circ}C$ for 120 min, but lost almost their activity in 30 min at $60^{\circ}C$. Zymography analysis of concentrated culture supernatant revealed one major band at 42 kDa and two faint bands at 68 and 120 kDa.